Believe it or not, many fluid artists do not want cells and struggle to achieve a cell-free painting. To understand how to NOT get cells, it is helpful to first understand the science behind getting cells.
David Alfaro Siqueiros could be called the father of acrylic pouring. He was a well-known Mexican muralist who discovered his “accidental painting” technique in the 1930s. He described his technique in a letter:
“When pouring layers of paint, of different colors, they infiltrate into each other. They produce the most magical fantasies and forms that the human mind can imagine.”
Siqueiros believed that the fluid itself created the painting, and he was right! His work (and ours) is a beautiful fusion of art and science.
Siqueiros’ technique for getting cells leverages the Rayleigh-Taylor instability: the instability that happens when fluids (paints) of different densities (lighter and heavier) interact with each other. The pigments in paint are made of materials such as metals, and some are heavier than others. When you mix paint in the same fluid medium the pigments become similarly suspended and interact with each other.
Heavier paints (pigments) sink through colors that are less dense (lighter). When you swipe titanium white (heavy) over phthalocyanine blue (light), it will sink through and create cells. If you did the opposite (blue swiped over white), you probably wouldn’t. Be aware of paint density! If you do not want cells, layer lighter paints on top of heavier paints.
To get an idea about paint densities, you can refer to the paint density information published by Golden for their acrylic paints. Even if you are not using Golden paints, their chart can provide a guide. Paint density won’t vary much across brands. You can always ask your preferred paints’ customer service departments if they provide similar reference materials.
Even if you have been careful to ensure the lighter paints stay on top of paints with a higher density, as you pour and tilt, colors can move, overlap, and interact. Slow tilting and plenty of paint can help minimize this to some degree. In my experience, using thicker paint and an appropriate technique helps keep paintings cell-free.
Also, adding a base layer of paint slicks up the canvas and helps the paint flow without overlapping as much. Some forms of pouring such as puddle pours or tree-ring pours allow greater control over paint interaction and movement. A flip cup is not your best option if you do NOT want cells. If you do not want cells, use a technique that makes cells less likely, experiment to find the best consistency, use enough paint so you don’t have to overtilt, slick up your canvas, and tilt slowly.
If you are going for no cells, air bubbles will be your nemesis. When air bubbles pop, they create little cells that can potentially become big cells. Air bubbles are created when you stir the paint, and you can create an excess if you stir the paint too fast. The air bubbles will dissipate if you allow the (slowly) mixed paints to sit for a day or so. If I mix paint too fast and then pour right away, I get lots of air bubbles. The photo above shows the effects of air bubbles! If you do not want cells, mix your paints slowly and then let them sit 24 hours.
Most people who start out are looking to create cells. We become obsessed with testing various additives, such as silicone, dimethicone, or alcohol. These additives help with the cell process. If you do not want cells, do not use additives like silicone or alcohol.
In my experience, some pouring mediums are better than others if you don’t want cells. I have found that Liquitex makes less cells than floetrol, and I think GAC 800 is the best of all when you don’t want cells. If you do not want cells, experiment with fluid mediums and see what works best for you.
Good luck to all of you on the quest for no cells and/or cells! It may take a bit of experimentation, but isn’t that a huge part of the joy?! Embrace your inner experimental fluid mechanic like Siqueiros! Happy pouring!